summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/iTCO_vendor_support.c
blob: b6b2f90b5d443c85f08c10e7a68de0f1b25942f4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
/*
 *	intel TCO vendor specific watchdog driver support
 *
 *	(c) Copyright 2006-2009 Wim Van Sebroeck <wim@iguana.be>.
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 *
 *	Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
 *	provide warranty for any of this software. This material is
 *	provided "AS-IS" and at no charge.
 */

/*
 *	Includes, defines, variables, module parameters, ...
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

/* Module and version information */
#define DRV_NAME	"iTCO_vendor_support"
#define DRV_VERSION	"1.04"

/* Includes */
#include <linux/module.h>		/* For module specific items */
#include <linux/moduleparam.h>		/* For new moduleparam's */
#include <linux/types.h>		/* For standard types (like size_t) */
#include <linux/errno.h>		/* For the -ENODEV/... values */
#include <linux/kernel.h>		/* For printk/panic/... */
#include <linux/init.h>			/* For __init/__exit/... */
#include <linux/ioport.h>		/* For io-port access */
#include <linux/io.h>			/* For inb/outb/... */

#include "iTCO_vendor.h"

/* List of vendor support modes */
/* SuperMicro Pentium 3 Era 370SSE+-OEM1/P3TSSE */
#define SUPERMICRO_OLD_BOARD	1
/* SuperMicro Pentium 4 / Xeon 4 / EMT64T Era Systems */
#define SUPERMICRO_NEW_BOARD	2
/* Broken BIOS */
#define BROKEN_BIOS		911

static int vendorsupport;
module_param(vendorsupport, int, 0);
MODULE_PARM_DESC(vendorsupport, "iTCO vendor specific support mode, default="
			"0 (none), 1=SuperMicro Pent3, 2=SuperMicro Pent4+, "
							"911=Broken SMI BIOS");

/*
 *	Vendor Specific Support
 */

/*
 *	Vendor Support: 1
 *	Board: Super Micro Computer Inc. 370SSE+-OEM1/P3TSSE
 *	iTCO chipset: ICH2
 *
 *	Code contributed by: R. Seretny <lkpatches@paypc.com>
 *	Documentation obtained by R. Seretny from SuperMicro Technical Support
 *
 *	To enable Watchdog function:
 *	    BIOS setup -> Power -> TCO Logic SMI Enable -> Within5Minutes
 *	    This setting enables SMI to clear the watchdog expired flag.
 *	    If BIOS or CPU fail which may cause SMI hang, then system will
 *	    reboot. When application starts to use watchdog function,
 *	    application has to take over the control from SMI.
 *
 *	    For P3TSSE, J36 jumper needs to be removed to enable the Watchdog
 *	    function.
 *
 *	    Note: The system will reboot when Expire Flag is set TWICE.
 *	    So, if the watchdog timer is 20 seconds, then the maximum hang
 *	    time is about 40 seconds, and the minimum hang time is about
 *	    20.6 seconds.
 */

static void supermicro_old_pre_start(struct resource *smires)
{
	unsigned long val32;

	/* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI# */
	val32 = inl(smires->start);
	val32 &= 0xffffdfff;	/* Turn off SMI clearing watchdog */
	outl(val32, smires->start);	/* Needed to activate watchdog */
}

static void supermicro_old_pre_stop(struct resource *smires)
{
	unsigned long val32;

	/* Bit 13: TCO_EN -> 1 = Enables the TCO logic to generate SMI# */
	val32 = inl(smires->start);
	val32 |= 0x00002000;	/* Turn on SMI clearing watchdog */
	outl(val32, smires->start);	/* Needed to deactivate watchdog */
}

/*
 *	Vendor Support: 2
 *	Board: Super Micro Computer Inc. P4SBx, P4DPx
 *	iTCO chipset: ICH4
 *
 *	Code contributed by: R. Seretny <lkpatches@paypc.com>
 *	Documentation obtained by R. Seretny from SuperMicro Technical Support
 *
 *	To enable Watchdog function:
 *	 1. BIOS
 *	  For P4SBx:
 *	  BIOS setup -> Advanced -> Integrated Peripherals -> Watch Dog Feature
 *	  For P4DPx:
 *	  BIOS setup -> Advanced -> I/O Device Configuration -> Watch Dog
 *	 This setting enables or disables Watchdog function. When enabled, the
 *	 default watchdog timer is set to be 5 minutes (about 4m35s). It is
 *	 enough to load and run the OS. The application (service or driver) has
 *	 to take over the control once OS is running up and before watchdog
 *	 expires.
 *
 *	 2. JUMPER
 *	  For P4SBx: JP39
 *	  For P4DPx: JP37
 *	  This jumper is used for safety.  Closed is enabled. This jumper
 *	  prevents user enables watchdog in BIOS by accident.
 *
 *	 To enable Watch Dog function, both BIOS and JUMPER must be enabled.
 *
 *	The documentation lists motherboards P4SBx and P4DPx series as of
 *	20-March-2002. However, this code works flawlessly with much newer
 *	motherboards, such as my X6DHR-8G2 (SuperServer 6014H-82).
 *
 *	The original iTCO driver as written does not actually reset the
 *	watchdog timer on these machines, as a result they reboot after five
 *	minutes.
 *
 *	NOTE: You may leave the Watchdog function disabled in the SuperMicro
 *	BIOS to avoid a "boot-race"... This driver will enable watchdog
 *	functionality even if it's disabled in the BIOS once the /dev/watchdog
 *	file is opened.
 */

/* I/O Port's */
#define SM_REGINDEX	0x2e	/* SuperMicro ICH4+ Register Index */
#define SM_DATAIO	0x2f	/* SuperMicro ICH4+ Register Data I/O */

/* Control Register's */
#define SM_CTLPAGESW	0x07	/* SuperMicro ICH4+ Control Page Switch */
#define SM_CTLPAGE	0x08	/* SuperMicro ICH4+ Control Page Num */

#define SM_WATCHENABLE	0x30	/* Watchdog enable: Bit 0: 0=off, 1=on */

#define SM_WATCHPAGE	0x87	/* Watchdog unlock control page */

#define SM_ENDWATCH	0xAA	/* Watchdog lock control page */

#define SM_COUNTMODE	0xf5	/* Watchdog count mode select */
				/* (Bit 3: 0 = seconds, 1 = minutes */

#define SM_WATCHTIMER	0xf6	/* 8-bits, Watchdog timer counter (RW) */

#define SM_RESETCONTROL	0xf7	/* Watchdog reset control */
				/* Bit 6: timer is reset by kbd interrupt */
				/* Bit 7: timer is reset by mouse interrupt */

static void supermicro_new_unlock_watchdog(void)
{
	/* Write 0x87 to port 0x2e twice */
	outb(SM_WATCHPAGE, SM_REGINDEX);
	outb(SM_WATCHPAGE, SM_REGINDEX);
	/* Switch to watchdog control page */
	outb(SM_CTLPAGESW, SM_REGINDEX);
	outb(SM_CTLPAGE, SM_DATAIO);
}

static void supermicro_new_lock_watchdog(void)
{
	outb(SM_ENDWATCH, SM_REGINDEX);
}

static void supermicro_new_pre_start(unsigned int heartbeat)
{
	unsigned int val;

	supermicro_new_unlock_watchdog();

	/* Watchdog timer setting needs to be in seconds*/
	outb(SM_COUNTMODE, SM_REGINDEX);
	val = inb(SM_DATAIO);
	val &= 0xF7;
	outb(val, SM_DATAIO);

	/* Write heartbeat interval to WDOG */
	outb(SM_WATCHTIMER, SM_REGINDEX);
	outb((heartbeat & 255), SM_DATAIO);

	/* Make sure keyboard/mouse interrupts don't interfere */
	outb(SM_RESETCONTROL, SM_REGINDEX);
	val = inb(SM_DATAIO);
	val &= 0x3f;
	outb(val, SM_DATAIO);

	/* enable watchdog by setting bit 0 of Watchdog Enable to 1 */
	outb(SM_WATCHENABLE, SM_REGINDEX);
	val = inb(SM_DATAIO);
	val |= 0x01;
	outb(val, SM_DATAIO);

	supermicro_new_lock_watchdog();
}

static void supermicro_new_pre_stop(void)
{
	unsigned int val;

	supermicro_new_unlock_watchdog();

	/* disable watchdog by setting bit 0 of Watchdog Enable to 0 */
	outb(SM_WATCHENABLE, SM_REGINDEX);
	val = inb(SM_DATAIO);
	val &= 0xFE;
	outb(val, SM_DATAIO);

	supermicro_new_lock_watchdog();
}

static void supermicro_new_pre_set_heartbeat(unsigned int heartbeat)
{
	supermicro_new_unlock_watchdog();

	/* reset watchdog timeout to heartveat value */
	outb(SM_WATCHTIMER, SM_REGINDEX);
	outb((heartbeat & 255), SM_DATAIO);

	supermicro_new_lock_watchdog();
}

/*
 *	Vendor Support: 911
 *	Board: Some Intel ICHx based motherboards
 *	iTCO chipset: ICH7+
 *
 *	Some Intel motherboards have a broken BIOS implementation: i.e.
 *	the SMI handler clear's the TIMEOUT bit in the TC01_STS register
 *	and does not reload the time. Thus the TCO watchdog does not reboot
 *	the system.
 *
 *	These are the conclusions of Andriy Gapon <avg@icyb.net.ua> after
 *	debugging: the SMI handler is quite simple - it tests value in
 *	TCO1_CNT against 0x800, i.e. checks TCO_TMR_HLT. If the bit is set
 *	the handler goes into an infinite loop, apparently to allow the
 *	second timeout and reboot. Otherwise it simply clears TIMEOUT bit
 *	in TCO1_STS and that's it.
 *	So the logic seems to be reversed, because it is hard to see how
 *	TIMEOUT can get set to 1 and SMI generated when TCO_TMR_HLT is set
 *	(other than a transitional effect).
 *
 *	The only fix found to get the motherboard(s) to reboot is to put
 *	the glb_smi_en bit to 0. This is a dirty hack that bypasses the
 *	broken code by disabling Global SMI.
 *
 *	WARNING: globally disabling SMI could possibly lead to dramatic
 *	problems, especially on laptops! I.e. various ACPI things where
 *	SMI is used for communication between OS and firmware.
 *
 *	Don't use this fix if you don't need to!!!
 */

static void broken_bios_start(struct resource *smires)
{
	unsigned long val32;

	val32 = inl(smires->start);
	/* Bit 13: TCO_EN     -> 0 = Disables TCO logic generating an SMI#
	   Bit  0: GBL_SMI_EN -> 0 = No SMI# will be generated by ICH. */
	val32 &= 0xffffdffe;
	outl(val32, smires->start);
}

static void broken_bios_stop(struct resource *smires)
{
	unsigned long val32;

	val32 = inl(smires->start);
	/* Bit 13: TCO_EN     -> 1 = Enables TCO logic generating an SMI#
	   Bit  0: GBL_SMI_EN -> 1 = Turn global SMI on again. */
	val32 |= 0x00002001;
	outl(val32, smires->start);
}

/*
 *	Generic Support Functions
 */

void iTCO_vendor_pre_start(struct resource *smires,
			   unsigned int heartbeat)
{
	switch (vendorsupport) {
	case SUPERMICRO_OLD_BOARD:
		supermicro_old_pre_start(smires);
		break;
	case SUPERMICRO_NEW_BOARD:
		supermicro_new_pre_start(heartbeat);
		break;
	case BROKEN_BIOS:
		broken_bios_start(smires);
		break;
	}
}
EXPORT_SYMBOL(iTCO_vendor_pre_start);

void iTCO_vendor_pre_stop(struct resource *smires)
{
	switch (vendorsupport) {
	case SUPERMICRO_OLD_BOARD:
		supermicro_old_pre_stop(smires);
		break;
	case SUPERMICRO_NEW_BOARD:
		supermicro_new_pre_stop();
		break;
	case BROKEN_BIOS:
		broken_bios_stop(smires);
		break;
	}
}
EXPORT_SYMBOL(iTCO_vendor_pre_stop);

void iTCO_vendor_pre_keepalive(struct resource *smires, unsigned int heartbeat)
{
	if (vendorsupport == SUPERMICRO_NEW_BOARD)
		supermicro_new_pre_set_heartbeat(heartbeat);
}
EXPORT_SYMBOL(iTCO_vendor_pre_keepalive);

void iTCO_vendor_pre_set_heartbeat(unsigned int heartbeat)
{
	if (vendorsupport == SUPERMICRO_NEW_BOARD)
		supermicro_new_pre_set_heartbeat(heartbeat);
}
EXPORT_SYMBOL(iTCO_vendor_pre_set_heartbeat);

int iTCO_vendor_check_noreboot_on(void)
{
	switch (vendorsupport) {
	case SUPERMICRO_OLD_BOARD:
		return 0;
	default:
		return 1;
	}
}
EXPORT_SYMBOL(iTCO_vendor_check_noreboot_on);

static int __init iTCO_vendor_init_module(void)
{
	pr_info("vendor-support=%d\n", vendorsupport);
	return 0;
}

static void __exit iTCO_vendor_exit_module(void)
{
	pr_info("Module Unloaded\n");
}

module_init(iTCO_vendor_init_module);
module_exit(iTCO_vendor_exit_module);

MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>, "
		"R. Seretny <lkpatches@paypc.com>");
MODULE_DESCRIPTION("Intel TCO Vendor Specific WatchDog Timer Driver Support");
MODULE_VERSION(DRV_VERSION);
MODULE_LICENSE("GPL");

OpenPOWER on IntegriCloud